EAST TENNESSEE GEOLOGICAL SOCIETY
April 2022 Virtual Meeting
Monday,
April 11, 2021
6:00 - 7:30 pm
Note: ETGS members will receive an email with info for logging into the meeting.
Award Winning Student Presentations
Comparative Geochemical Analysis of Recent Volcanic Flows on Barva Volcano,
Costa Rica
By
Julie Marie Coulombe
Department of Earth and Planetary Science
MS Candidate
University of Tennessee, Knoxville
Abstract
Barva volcano is a dormant stratovolcano in the Cordillera Central
region of Costa Rica, rising above the capitol city of San Jose with
its population of 347,000. Barva's recent inactivity and extensive
forestation have resulted in fewer investigations of its
composition, petrogenesis and eruptive history. The objective of
this research is to analyze the geochemical data from several of the
most recent lava flows, evaluate variability between eruptive units,
and ascertain physical conditions within the Barva's magma storage
region. This study will help constrain the recent volcanic
stratigraphy of units seen in the quarry and provide information
regarding future eruptive behavior.
Here, a complete petrographic and geochemical analysis of nine
samples from young lava flows obtained from Tajo La Florida quarry
on the flank of Barva is presented. Results indicate all lava flow
samples are basaltic-andesites, with minimal major and minor element
variations between flows. Observed phase assemblages consist of
phenocrysts of plagioclase (11.2 mass%), two pyroxenes (3.6 mass%),
and FeTi oxides (<1 mass%) within a groundmass of glass and
plagioclase microlites. These results point to very little change in
Barva's magma storage conditions, which supports a continued period
of dormancy for Barva Volcano.
Biography
Julie is a
student at the University of Tennessee, where she transferred from
Pellissippi State Community College in 2017. She received her B.S.
in geology in 2019 and expects to graduate with her M.S. in geology
in 2022. She attended field camp at Hawai'i Volcanoes National Park,
and studies volcanoes, subduction zones and high-temperature igneous
petrology. Her graduate research has focused on the petrology of the
Barva Volcano in Costa Rica, and her research was presented at the
Geological Society of America's national conference in 2021. Julie
is from Bolton Vermont and spent ten years as an accountant at Keurig while raising twin daughters. She then spent nineteen months
traveling, living in six different cities in the United States.
During these travels she discovered her love of hiking and geology
while visiting 41 of the 63 US National Parks. Her favorite parks
are Yosemite and Mount Rainier, and she hopes to someday live and
work in the Pacific Northwest.
Structural Analysis of
Cross-Cutting and Curviplanar Veins in Gale crater, Mars and their Implications
for Basin Evolution
By
Morgan Lewis
Department of Earth and Planetary Science
PhD Candidate
University of Tennessee, Knoxville
Abstract
Gale crater is a 154-km wide impact crater along the
equatorial crustal dichotomy of Mars where the Curiosity rover
landing site and traverse are located. The geologic history of the
crater includes likely ancient lake stand(s) as well as a likely
climatic evolution implied by a transition from clay-bearing to
sulfate-bearing units as approaching the middle of the crater and
top of the central mound, Aeolis Mons. In particular, the mudstone
rich Blunts Point member of the Gale crater stratigraphy is overrun
with mineral (calcium sulfate) filled fractures or veins. These
veins occur in two prominent orientations, high angle or low angle,
with varied behavior as related to primary bedding planes.
Investigating these fractures can give scientists valuable
information about the basin history of Gale crater, and that's what
this project intends to do via fracture density calculations,
general fracture size analyses, and 3D reconstructions used to
measure fracture orientation and extrapolate likely stress fields of
their formation.
Biography
Morgan Lewis is a second year PhD student working with Dr. Chris Fedo at the University of Tennessee Knoxville. She was born and raised in east metro Atlanta and attended the University of Georgia for her undergraduate degree in Geology (finished in May 2020), but she has family ties to Knoxville and is excited to be experiencing East Tennessee for the next few years. She currently works as a MAHLI/MARDI Science Payload Uplink Lead on the Mars Science Laboratory team with the Curiosity rover, and her research interests include planetary geology, geochemistry, petrogenesis, and geologic mapping. She also has a passion for communicating science with the public and keeping scientific discoveries accessible to as many people as possible.
Greetings! We hope you will join us for the next ETGS virtual meeting, and that you, your family, and your colleagues are staying healthy and well.
As a courtesy, please mute your cell phone or the microphone in your laptop/tablet to minimize background noise and feedback echoes. We will try to mute all participants until the presentation is finished. Please use the chat feature to type comments or questions during the presentation. We recommend that you send questions for the speaker to "everyone" so all participants can see the question. After the presentation, the speaker will answer questions. During this Q&A period, you may unmute if you wish to ask a question verbally.
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Thank you for your patience and understanding as we continue adapting to this virtual format. As always, we welcome and appreciate your feedback and suggestions for improvement.
Page updated March 19, 2022 |